Speaking to NME magazine in the UK, this is what Dave had to say:
"Some of it's a little darker, some of it's a little faster," he recently told NME. "Being in this position right now, not knowing where we're gonna go or what we're gonna do, it's kind of like the world's ours to do what we want. Are we gonna go back to the speed and thrash metal roots that made us who we are? Are we gonna experiment and rely on the melody that we've discovered in Megadeth songs?"
Speaking on being more melodic than other thrash acts: "We've tried to do that in Megadeth, have a little melody so that it's not just the same old grinding music like everybody else has. We’re just happy to get going and get to the studio."
I would say don't expect new Megadeth until 2013 at the earliest. [via Guitar World